Xzthod of and appabatus fob softening wateb



June 5, 1923. v 1 I Re. 15,618

R. DUGGAN METHOD OF AND APPARATUS FOR SOFTENING WATER Original FiledOct. 23, 1916 y 15 solutions; and it also paratus with connectionsadapted for the 'psrformance of this method; all as more $5 oxid,tinoxid, zinc oxid, etc.),

.4. cium and magnesium .50 of water; and uniform mom a. accent,

or m roux, x. 2.,

I lie-15,618 PATENT HQFFICE.

OI mm ronx, N. Y.,'ASSIGNOB TO THE PEBMUTIT OOIPAFY, A OOBPOBATION OIDELAWARE.

- mnon or al rm-rue ro'n sonnms warns.

, am August 90, 1918, Serial No. 127,127, filed-October 28, 1916Application for reissue fled Apr-u 3!, 1822. Serial No. 556,131.

To all whom it may concern:

Be it known that I, Tnouas B. DUGGAN, a citizen of Great Britain,residing at New York, in the county of New York and State of New York,have invented certain new and useful Improvements in Methods of and Aparatus for Softenin Water, of which 810 followin is a speci cation. v

This invention re ates to methods of and apparatus for softenin water;and it comprises a method of utilizing the activity of exchangesilicates to a greater extent than is now the case and of quicklyrevivifying the same with good utilization of revivifying comprisescertain aplly hereinafter set forth and as claimed.

In the method of, softening water by the a use of exchange silicateswhich is now well known, water to be softened is passed through certainmaterials containing silica and alumina (or another amphoteric end, suchas titanium oxid, iron oxid, chromium alkali and water. These materialsare used in the form of small hard granules-which are employed as agranular bed. on the passage of hard water through the 80 bed ofgranules the lime and magnesia compounds, to which the water owes itshardness, are taken up by the exchange s licate, alkali compounds goinginto solution in their lieu. After a period ofuse when the exchangesilicate has. taken up a certain amount of lime and magnesia, it isrevivified by paming a solution of sodium chlorld (common salt) throughthe bed. The lime and magnesia now go into solution as calchlorids andthe exchange silicate takes up alkali again so that it is ready forre-use. v v I find certain advantages are gained. by an upward flow ofsalt solution in the re- I generating phase. With the relatively heavysalt solution passing in an upwar direction the relative movement of thegranules with regard to each other is. more pronounced than it is with asimilar flow solution takes place. 7 I

In revivification, it is found that the main of the absorbed bases willbe removed ythe salt solution after the regenerating can be absorbed by11 d ab partially revived passage of the salt liquid. has been sup liedto and assed through the layer p in an amount equ to or than that amountof liquid which stored in the spaces between the granules. Or, in otherwords, the liquid occurring between the granules must be displaced onceor twice by'the' salt solution in order to remove the main part of thebases the exchan e silicate. Re sage of the used salt solution throughthe does little good and may do harm, sinaa such a solution will onlytake up a certain amount of calcium or magnesium before losingregenerating power. When in softening the water flows downward and thesalt solution passes upward, the 'lowerlayers of silicates arecompletely larger into contact therewith again. It is desirable inregeneration to bring the clean-or uncontaminated salt solution firstinto contact with the most active or least contaminated layers ofsilicates.

After the revivifying solution has been used on the exchange silicate,such solution must as already stated, he. removed to prevent thecontamination of the water next to be treated. In one way, giving autilization of the salt solution, I can, after admitting the saltsolution to the bed, gradually admit fresh water at the bottom of thebed, drawing oif from a point above; the admission of water beingfinally stopped and the residual liquid in the bed then removed byvdraining from the bottom. It is advantageous to choose the amount ofwater in which the regenerating salt is dissolved, so that the main artof the absorbed bases is taken into so ution and taken away before freshwater is introduced.

Other ways of removingethe salt solution than that indicated may used;.but the described way is economical and practical, since the wholeamount. of regenerating 'tauid is well utilizedbut any other suite waymay be used. Care should however .be' taken that repassage ofcontaminated salt solution through the revived or bed is avoided.

In the accompanying illustration-.1 have shown, more or lessdiagrammaticall certain embodiments of apparatus within the presentinvention and the described process.

susceptible of use in U revived first and it is inexpedlent to bringback contaminated brine I special 7 The figure illustrates a view of astructure wherein the flow of water to be soft ened is normally downwardwhile that of the re nerating solution is upward.

n the structure, element A, is a tank, pipe or other source of water tobe softened and treated, while D is a tank, pipe or other source of saltsolution. B is a casing for containing the bed of exchange silicates andis a pipe, tank or other arrangement for removing or receiving softenedwater. E is a diagrammatically shown sewer connection. I

Casing B contains a layer or bed 1 of exchange silicates. The granularsilicates may rest on a vel layer 4, or the gravel layer may be i sensed with. Cross-plate 5 may be replace by a strainer system or anyother suitable structure. Below this cross-plate is open chamber 6 withpipe connection 7 at its lowest point. Baflie'S is arranged above thispi e connection in order to give an even distribution of the liquid.Above the bed is an empty chamber 9 Leading from tank A is water pipe 10provided with valve 10'. Valved inlet 11 may be used inlieu of tank A asa source of water, to be softened. This pipe 10 extends downwardlyto across-connection 12 communieating with the casing B at the lowest point.

dmg from this cross-connection is another valved pi 13 leading to tank Dfor salt solution. I lieu of tank D salt solution may be brought fromanother source through valved in et 14. As shown, tank is provided witha salt box 15 having perforated bottom 16. Also leading from thewatersupply pipe is another cross pipe 16 provide wit valved outlet pipe17 leadmg to the tank D for salt solution. As shown this-pi is alsoprovided with a float valve 18. eyond this valved outletpi 17 in theupper cross ipe is valve 191m beyond this'again is a own pipe 20 leadinginto the top of casing B. v

The up er' cross pipe is further provided with a va ve 29 beyond whichit extends to connection 30 and 31 leadin down the sewer connection E,thus a ording a discharge for the back wash Water. The lower cross pipe12 has a connection entering the bottom of the casing B but at thispointit has another connection 32 leading past valve 33 to the sewerconnection E. Another valved connection 34 leads through pipe 35 to tankC for softened water.

n the operation of this structure, presuming the exchange silicateerated and ready for operation, water from 11 or A passes through 16'and 20, valve 19 being open, into chamber 9, and thence through thesilicate bed 1 downward to 7. ened water passes through When theexchange silicate regeneration, the flow of water From 7 the soft 34 and35 to C. n

I valve in 17 is o v the bed to flow and go to exit ingclosed, .19 maybe 0 V the to be regenthrough the apparatus isstopped and the pened, box15 being supplied with the requisite amount of salt. An amount of watercontrolled by float valve 18 enters D and dissolves the salt in the saltbox. Brine from anoth course be supplied through pipe 14. The saltsolution passes downward throu h 13 (valves 10 and 19 being closed) am?into the bottom of the casing B through'7. The salt solution passesupward through silicates 1 to the 'draw-ofl cock 25and thence through 26to waste. f

In flushing out the brine water may of course be sent through the saltline coming through line 16 andpipe 17 past valve 18 into D and thencedownwardly through 13, past valve 13' the casing B through pipe 7. In sodoing, a simple manner of operation isaiforded 811100 the necessaryquantity of saltma be put into box 15 and then thewater allowed to tionnecessary for reviving and then asses this salt solution upwardly throngthe.-

silicates to waste at 25 and then washes the whole apparatus. Or valve24 ma be opened to allow air to enter, valve 10" closed and valve 33pened allowing the liquid in downward through the mass at 7 and 32. Itwill be noted that 7 communicates with B at the lowest portion of thecasing soa'sto insure a positive draining with removal of all watercontaining salt. If desired, the valve 24 bepened and a supply of freshwater sent through the mass downwardly for washingpurposes. The exchangesilicate being new revived and washed is ready for another watersoftening phase as before.

With an operation such as that described, the dissolved impurities inthe water to which-itowes its hardness (lime or magnesia or both) mainlyaccumulate in the face of the .bed at which the water enters, the toface. On-now passing salt solution throug from the opposite face,.this'salt solution, which is of course, substantially free of lime andmagnesia, passes first through the little contaminated portion of theinto contact with the contaminated portion, there taking up the lime andmagnesia. As flow continues, the dissolved lime and magnesia arecarried. away from the bed and do not reenterit.

What I claim is:

1. In the purification and softening of water, the process whichcomprises transmitting water downwardly through a granular bed ofexchange silicates until such silicates have functioned to a suflicientdegree, thereupon passing salt solution followed by wash water throughsuch bed in an upward direction with removal of salt soluer source mayof shown into the bottom of l i i I The water at first forms the saltsolubed and then tion and wash water at or above the upper face of suchbed until the silicates are regenerated, interrupting the flow at thistime and draining the bed from the lowest point, and

5 once more assing water to be softened throulgh the d in a downwarddirection.

2. n a water softening apparatus, a casing, a bed of exchange silicatestherein,

means for transmitting water to be softened 10 through such bed andmeans for passing salt solution through the bed upwardly to a point ofoutlet above such bed, means for washing out the salt solution and meanscon nected to the lowest int of the casing lead ing to a place ofdisposition for removing the water used in such washing out.

In testimony whereof I affix my signature.

THOMAS R. DUGGAN.

